Smart antenna technology may sufficiently utilize spatial characteristics of wireless resources to improve a wireless resource utilization of a wireless mobile communication system and improve the system capacity fundamentally. As a core technology of the smart antenna technology, beamforming is mainly adapted to eliminate interference between cells and improve a cell-edge user performance.
Multiple mechanisms for adjacent cell interference coordination based on beamforming are provided in a Long Term Evolution-Advanced Coordinated Multi-Point (LTE-A CoMP). A best/worst precoding matrix mechanism requires a User Equipment (UE) to report best/worst Precoding Matrix Indicators (PMIs) of the cell and adjacent cells thereof.
However, when the best/worst precoding matrix mechanism requires the UE to report PMIs of the adjacent cells, the UE firstly performs a cell searching on the adjacent cells, obtains the PMIs of the adjacent cells after synchronizing, and report the PMIs to a service base station of the cells. However, frequent reporting the PMIs of the adjacent cells by the UE will greatly increase an uplink overhead.